Without any third-party tool, the user can't import a Zimbra mailbox to Outlook account. So it is highly recommended you go with the MailsDaddy Zimbra Converter tool (aka Zimbra to Outlook converter). The software has several features to migrate data from Zimbra to Outlook PST. It manages all folders, emails, contacts, calendars, tasks, and various other items without any technical hurdles. The software comes with the free demo edition of the software that converts up to 20 emails from each folder
Get more info: Zimbra Converter Tool